Display device and manufacturing method of display device

ABSTRACT

According to one embodiment, a manufacturing method of a display device includes preparing a processing substrate by forming a lower electrode, forming a rib, and forming a partition including a lower portion and an upper portion, forming an organic layer on the lower electrode, forming an upper electrode on the organic layer, forming a first transparent layer on the upper electrode, and forming a second transparent layer on the first transparent layer. The first transparent layer and the second transparent layer are formed of organic materials different from each other. A refractive index of the second transparent layer is less than a refractive index of the first transparent layer.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. application Ser.No. 18/336,048, filed Jun. 16, 2023, which is based upon and claims thebenefit of priority from Japanese Patent Application No. 2022-098019,filed Jun. 17, 2022, the entire contents of each are incorporated hereinby reference.

FIELD

Embodiments described herein relate generally to a display device and amanufacturing method of a display device.

BACKGROUND

Recently, display devices to which an organic light emitting diode(OLED) is applied as a display element have been put into practical use.This display element comprises a pixel circuit including a thin-filmtransistor, a lower electrode connected to the pixel circuit, an organiclayer which covers the lower electrode, and an upper electrode whichcovers the organic layer. The organic layer includes functional layerssuch as a hole transport layer and an electron transport layer inaddition to a light emitting layer.

In the process of manufacturing such a display element, a techniquewhich prevents the reduction in reliability has been required.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing a configuration example of a display deviceDSP.

FIG. 2 is a diagram showing an example of the layout of subpixels SP1,SP2 and SP3.

FIG. 3 is a schematic cross-sectional view of the display device DSPalong the A-B line of FIG. 2 .

FIG. 4 is a diagram showing an example of the configuration of displayelements 201 to 203.

FIG. 5 is a flow diagram for explaining an example of the manufacturingmethod of the display device DSP.

FIG. 6 is a diagram for explaining the manufacturing method of thedisplay device DSP.

FIG. 7 is a diagram for explaining the manufacturing method of thedisplay device DSP.

FIG. 8 is a diagram for explaining the manufacturing method of thedisplay device DSP.

FIG. 9 is a diagram for explaining the manufacturing method of thedisplay device DSP.

FIG. 10 is a diagram for explaining the manufacturing method of thedisplay device DSP.

FIG. 11 is a diagram for explaining the manufacturing method of thedisplay device DSP.

FIG. 12 is a diagram for explaining the manufacturing method of thedisplay device DSP.

DETAILED DESCRIPTION

Embodiments described herein aim to provide a display device which canprevent the reduction in reliability and a manufacturing method of sucha display device.

In general, according to one embodiment, a manufacturing method of adisplay device comprises preparing a processing substrate by forming alower electrode above a substrate, forming a rib comprising an apertureoverlapping the lower electrode, and forming a partition including alower portion located on the rib and an upper portion located on thelower portion and protruding from a side surface of the lower portion,forming an organic layer on the lower electrode in the aperture, formingan upper electrode on the organic layer, forming a first transparentlayer on the upper electrode, and forming a second transparent layer onthe first transparent layer. The first transparent layer and the secondtransparent layer are formed of organic materials different from eachother. A refractive index of the second transparent layer is less than arefractive index of the first transparent layer.

According to another embodiment, a display device comprises a substrate,a lower electrode provided above the substrate, a rib formed of aninorganic insulating material and comprising an aperture overlapping thelower electrode, a partition comprising a lower portion provided on therib and formed of a conductive material, and an upper portion providedon the lower portion and protruding from a side surface of the lowerportion, an organic layer provided on the lower electrode in theaperture, an upper electrode which is provided on the organic layer andis in contact with the lower portion of the partition, a firsttransparent layer provided on the upper electrode, a second transparentlayer provided on the first transparent layer, and a sealing layer whichcovers the second transparent layer and is in contact with the lowerportion of the partition. The first transparent layer and the secondtransparent layer are formed of organic materials different from eachother. A refractive index of the first transparent layer is greater thana refractive index of the second transparent layer.

The embodiments can provide a display device which can prevent thereduction in reliability and a manufacturing method of such a displaydevice.

Embodiments will be described with reference to the accompanyingdrawings.

The disclosure is merely an example, and proper changes in keeping withthe spirit of the invention, which are easily conceivable by a person ofordinary skill in the art, come within the scope of the invention as amatter of course. In addition, in some cases, in order to make thedescription clearer, the widths, thicknesses, shapes, etc., of therespective parts are illustrated schematically in the drawings, ratherthan as an accurate representation of what is implemented. However, suchschematic illustration is merely exemplary, and in no way restricts theinterpretation of the invention. In addition, in the specification anddrawings, structural elements which function in the same or a similarmanner to those described in connection with preceding drawings aredenoted by like reference numbers, detailed description thereof beingomitted unless necessary.

In the drawings, in order to facilitate understanding, an X-axis, aY-axis and a Z-axis orthogonal to each other are shown depending on theneed. A direction parallel to the X-axis is referred to as a firstdirection. A direction parallel to the Y-axis is referred to as a seconddirection. A direction parallel to the Z-axis is referred to as a thirddirection. When various elements are viewed parallel to the thirddirection Z, the appearance is defined as a plan view.

The display device of the present embodiment is an organicelectroluminescent display device comprising an organic light emittingdiode (OLED) as a display element, and could be mounted on a television,a personal computer, a vehicle-mounted device, a tablet, a smartphone, amobile phone, etc.

FIG. 1 is a diagram showing a configuration example of a display deviceDSP.

The display device DSP comprises a display area DA which displays animage and a surrounding area SA around the display area DA on aninsulating substrate 10. The substrate 10 may be glass or a resinousfilm having flexibility.

In the present embodiment, the substrate 10 is rectangular as seen inplan view. It should be noted that the shape of the substrate 10 in planview is not limited to a rectangular shape and may be another shape suchas a square shape, a circular shape or an elliptic shape.

The display area DA comprises a plurality of pixels PX arrayed in matrixin a first direction X and a second direction Y. Each pixel PX includesa plurality of subpixels SP. For example, each pixel PX includessubpixel SP1 which exhibits a first color, subpixel SP2 which exhibits asecond color and subpixel SP3 which exhibits a third color. The firstcolor, the second color and the third color are different colors. Eachpixel PX may include a subpixel SP which exhibits another color such aswhite in addition to subpixels SP1, SP2 and SP3 or instead of one ofsubpixels SP1, SP2 and SP3.

Each subpixel SP comprises a pixel circuit 1 and a display element 20driven by the pixel circuit 1. The pixel circuit 1 comprises a pixelswitch 2, a drive transistor 3 and a capacitor 4. The pixel switch 2 andthe drive transistor 3 are, for example, switching elements consistingof thin-film transistors.

The gate electrode of the pixel switch 2 is connected to a scanning lineGL. One of the source electrode and drain electrode of the pixel switch2 is connected to a signal line SL. The other one is connected to thegate electrode of the drive transistor 3 and the capacitor 4. In thedrive transistor 3, one of the source electrode and the drain electrodeis connected to a power line PL and the capacitor 4, and the other oneis connected to the anode of the display element 20.

It should be noted that the configuration of the pixel circuit 1 is notlimited to the example shown in the figure. For example, the pixelcircuit 1 may comprise more thin-film transistors and capacitors.

The display element 20 is an organic light emitting diode (OLED) as alight emitting element, and may be called an organic EL element.

FIG. 2 is a diagram showing an example of the layout of subpixels SP1,SP2 and SP3.

In the example of FIG. 2 , subpixels SP2 and SP3 are arranged in thesecond direction Y. Further, each of subpixels SP2 and SP3 is adjacentto subpixel SP1 in the first direction X.

When subpixels SP1, SP2 and SP3 are provided in line with this layout,in the display area DA, a column in which subpixels SP2 and SP3 arealternately provided in the second direction Y and a column in which aplurality of subpixels SP1 are provided in the second direction Y areformed. These columns are alternately arranged in the first direction X.

It should be noted that the layout of subpixels SP1, SP2 and SP3 is notlimited to the example of FIG. 2 . As another example, subpixels SP1,SP2 and SP3 in each pixel PX may be arranged in order in the firstdirection X.

A rib 5 and a partition 6 are provided in the display area DA. The rib 5comprises apertures AP1, AP2 and AP3 in subpixels SP1, SP2 and SP3,respectively.

The partition 6 overlaps the rib 5 as seen in plan view. The partition 6comprises a plurality of first partitions 6 x extending in the firstdirection X and a plurality of second partitions 6 y extending in thesecond direction Y. The first partitions 6 x are provided between theapertures AP2 and AP3 which are adjacent to each other in the seconddirection Y and between two apertures AP1 which are adjacent to eachother in the second direction Y. Each second partition 6 y is providedbetween the apertures AP1 and AP2 which are adjacent to each other inthe first direction X and between the apertures AP1 and AP3 which areadjacent to each other in the first direction X.

In the example of FIG. 2 , the first partitions 6 x and the secondpartitions 6 y are connected to each other. Thus, the partition 6 isformed into a grating shape surrounding the apertures AP1, AP2 and AP3as a whole. In other words, the partition 6 comprises apertures insubpixels SP1, SP2 and SP3 in a manner similar to that of the rib 5.

Subpixels SP1, SP2 and SP3 comprise display elements 201, 202 and 203,respectively, as the display elements 20.

Subpixel SP1 comprises a lower electrode LE1, an upper electrode UE1 andan organic layer OR1 overlapping the aperture AP1. Subpixel SP2comprises a lower electrode LE2, an upper electrode UE2 and an organiclayer OR2 overlapping the aperture AP2. Subpixel SP3 comprises a lowerelectrode LE3, an upper electrode UE3 and an organic layer OR3overlapping the aperture AP3.

In the example of FIG. 2 , the outer shapes of the lower electrodes LE1,LE2 and LE3 are shown by dotted lines, and the outer shapes of theorganic layers OR1, OR2 and OR3 and the upper electrodes UE1, UE2 andUE3 are shown by alternate long and short dash lines. The peripheralportion of each of the lower electrodes LE1, LE2 and LE3 overlaps therib 5. It should be noted that the outer shape of each of the lowerelectrodes, organic layers and upper electrodes shown in the figure doesnot necessarily reflect the accurate shape.

The lower electrode LE1, the upper electrode UE1 and the organic layerOR1 constitute the display element 201 of subpixel SP1. The lowerelectrode LE2, the upper electrode UE2 and the organic layer OR2constitute the display element 202 of subpixel SP2. The lower electrodeLE3, the upper electrode UE3 and the organic layer OR3 constitute thedisplay element 203 of subpixel SP3.

The lower electrodes LE1, LE2 and LE3 correspond to, for example, theanodes of the display elements. The upper electrodes UE1, UE2 and UE3correspond to the cathodes of the display elements or a commonelectrode.

The lower electrode LE1 is connected to the pixel circuit 1 (see FIG. 1) of subpixel SP1 through a contact hole CH1. The lower electrode LE2 isconnected to the pixel circuit 1 of subpixel SP2 through a contact holeCH2. The lower electrode LE3 is connected to the pixel circuit 1 ofsubpixel SP3 through a contact hole CH3.

In the example of FIG. 2 , the area of the aperture AP1 is greater thanthat of the aperture AP2, and the area of the aperture AP2 is greaterthan that of the aperture AP3. In other words, the area of the lowerelectrode LE1 exposed from the aperture AP1 is greater than that of thelower electrode LE2 exposed from the aperture AP2. The area of the lowerelectrode LE2 exposed from the aperture AP2 is greater than that of thelower electrode LE3 exposed from the aperture AP3.

For example, the display element 201 of subpixel SP1 is configured toemit light in a blue wavelength range. The display element 202 ofsubpixel SP2 is configured to emit light in a green wavelength range.The display element 203 of subpixel SP3 is configured to emit light in ared wavelength range.

FIG. 3 is a schematic cross-sectional view of the display device DSPalong the A-B line of FIG. 2 .

A circuit layer 11 is provided on the substrate 10 described above. Thecircuit layer 11 includes various circuits such as the pixel circuit 1,and various lines such as scanning line GL, signal line SL and powerline PL shown in FIG. 1 . The circuit layer 11 is covered with aninsulating layer 12. The insulating layer 12 functions as aplanarization film which planarizes the irregularities formed by thecircuit layer 11.

The lower electrodes LE1, LE2 and LE3 are provided on the insulatinglayer 12. The rib 5 is provided on the insulating layer 12 and the lowerelectrodes LE1, LE2 and LE3. The end portions of the lower electrodesLE1, LE2 and LE3 are covered with the rib 5. In other words, the endportions of the lower electrodes LE1, LE2 and LE3 are provided betweenthe insulating layer 12 and the rib 5. Of the lower electrodes LE1, LE2and LE3, between the lower electrodes which are adjacent to each other,the insulating layer 12 is covered with the rib 5.

The partition 6 includes a lower portion (stem) 61 provided on the rib 5and an upper portion (shade) 62 provided on the lower portion 61. Thelower portion 61 of the partition 6 shown on the left side of the figureis located between the aperture AP1 and the aperture AP2. The lowerportion 61 of the partition 6 shown on the right side of the figure islocated between the aperture AP2 and the aperture AP3. The upper portion62 has a width greater than that of the lower portion 61. By thisconfiguration, the both end portions of the upper portion 62 protruderelative to the side surfaces of the lower portion 61. This shape of thepartition 6 may be called an overhang shape. Of the upper portion 62, aportion which protrudes to the aperture AP1 relative to the lowerportion 61 is referred to as a protrusion 621. A portion which protrudesto the aperture AP2 relative to the lower portion 61 is referred to as aprotrusion 622. A portion which protrudes to the aperture AP3 relativeto the lower portion 61 is referred to as a protrusion 623.

The organic layer OR1 is in contact with the lower electrode LE1 throughthe aperture AP1, covers the lower electrode LE1 and overlaps part ofthe rib 5. The upper electrode UE1 faces the lower electrode LE1 and isprovided on the organic layer OR1. Further, the upper electrode UE1 isin contact with a side surface of the lower portion 61. The organiclayer OR1 and the upper electrode UE1 are located on the lower siderelative to the upper portion 62.

The organic layer OR2 is in contact with the lower electrode LE2 throughthe aperture AP2, covers the lower electrode LE2 and overlaps part ofthe rib 5. The upper electrode UE2 faces the lower electrode LE2 and isprovided on the organic layer OR2. Further, the upper electrode UE2 isin contact with a side surface of the lower portion 61. The organiclayer OR2 and the upper electrode UE2 are located on the lower siderelative to the upper portion 62.

The organic layer OR3 is in contact with the lower electrode LE3 throughthe aperture AP3, covers the lower electrode LE3 and overlaps part ofthe rib 5. The upper electrode UE3 faces the lower electrode LE3 and isprovided on the organic layer OR3. Further, the upper electrode UE3 isin contact with a side surface of the lower portion 61. The organiclayer OR3 and the upper electrode UE3 are located on the lower siderelative to the upper portion 62.

Subpixels SP1, SP2 and SP3 further include cap layers (opticaladjustment layers) CP1, CP2 and CP3 for adjusting the optical propertyof the light emitted from the light emitting layers of the organiclayers OR1, OR2 and OR3.

The cap layer CP1 is located in the aperture AP1, is located on thelower side relative to the upper portion 62 and is provided on the upperelectrode UE1. The cap layer CP2 is located in the aperture AP2, islocated on the lower side relative to the upper portion 62 and isprovided on the upper electrode UE2. The cap layer CP3 is located in theaperture AP3, is located on the lower side relative to the upper portion62 and is provided on the upper electrode UE3.

Sealing layers SE1, SE2 and SE3 are provided in subpixels SP1, SP2 andSP3, respectively.

The sealing layer SE1 is in contact with the cap layer CP1 and the lowerand upper portions 61 and 62 of the partition 6 and continuously coversthe members of subpixel SP1.

The sealing layer SE2 is in contact with the cap layer CP2 and the lowerand upper portions 61 and 62 of the partition 6 and continuously coversthe members of subpixel SP2.

The sealing layer SE3 is in contact with the cap layer CP3 and the lowerand upper portions 61 and 62 of the partition 6 and continuously coversthe members of subpixel SP3.

The sealing layers SE1, SE2 and SE3 are covered with a protective layer13.

In the example shown in the figure, part of the organic layer OR1, partof the upper electrode UE1 and part of the cap layer CP1 are locatedbetween the partition 6 and the sealing layer SE1, are provided on theupper portion 62 and are spaced apart from the portions located on thelower side relative to the upper portion 62.

Part of the organic layer OR2, part of the upper electrode UE2 and partof the cap layer CP2 are located between the partition 6 and the sealinglayer SE2, are provided on the upper portion 62 and are spaced apartfrom the portions located on the lower side relative to the upperportion 62.

Part of the organic layer OR3, part of the upper electrode UE3 and partof the cap layer CP3 are located between the partition 6 and the sealinglayer SE3, are provided on the upper portion 62 and are spaced apartfrom the portions located on the lower side relative to the upperportion 62.

The insulating layer 12 is an organic insulating layer. The rib 5 andthe sealing layers SE1, SE2 and SE3 are inorganic insulating layers.

The rib 5 is formed of silicon nitride (SiNx) as an example of inorganicinsulating materials. It should be noted that the rib 5 may be formedas, as another inorganic insulating material, a single-layer body of oneof silicon oxide (SiOx), silicon oxynitride (SiON) and aluminum oxide(Al₂O₃). The rib 5 may be formed as a sacked layer body of a combinationconsisting of at least two of a silicon nitride layer, a silicon oxidelayer, a silicon oxynitride layer and an aluminum oxide layer.

The sealing layers SE1, SE2 and SE3 are formed of, for example, the sameinorganic insulating material.

The sealing layers SE1, SE2 and SE3 are formed of silicon nitride (SiNx)as an example of inorganic insulating materials. It should be noted thatthe sealing layers SE1, SE2 and SE3 may be formed as, as anotherinorganic insulating material, a single-layer body of one of siliconoxide (SiOx), silicon oxynitride (SiON) and aluminum oxide (Al₂O₃). Eachof the sealing layers SE1, SE2 and SE3 may be formed as a stacked layerbody of a combination consisting of at least two of a silicon nitridelayer, a silicon oxide layer, a silicon oxynitride layer and an aluminumoxide layer. Thus, the sealing layers SE1, SE2 and SE3 may be formed ofthe same material as the rib 5.

The lower portion 61 of the partition 6 is formed of a conductivematerial and is electrically connected to the upper electrodes UE1, UE2and UE3. The upper portion 62 of the partition 6 may be also formed of aconductive material.

The thickness of the rib 5 is sufficiently less than that of each of thepartition 6 and the insulating layer 12. For example, the thickness ofthe rib 5 is greater than or equal to 200 nm but less than or equal to400 nm.

The thickness of the lower portion 61 of the partition 6 (the thicknessfrom the upper surface of the rib 5 to the lower surface of the upperportion 62) is greater than that of the rib 5.

The thickness of the sealing layer SE1, the thickness of the sealinglayer SE2 and the thickness of the sealing layer SE3 are substantiallyequal to each other and are, for example, greater than or equal to 1 μm.

Each of the lower electrodes LE1, LE2 and LE3 may be formed of atransparent conductive material such as ITO or may comprise a multilayerstructure of a metal material such as silver (Ag) and a transparentconductive material. Each of the upper electrodes UE1, UE2 and UE3 isformed of, for example, a metal material such as an alloy of magnesiumand silver (MgAg). Each of the upper electrodes UE1, UE2 and UE3 may beformed of a transparent conductive material such as ITO.

Each of the organic layers OR1, OR2 and OR3 includes a plurality offunctional layers such as a hole injection layer, a hole transportlayer, an electron blocking layer, a hole blocking layer, an electrontransport layer and an electron injection layer. The organic layer OR1includes a light emitting layer EM1. The organic layer OR2 includes alight emitting layer EM2. The light emitting layer EM2 is formed of amaterial different from that of the light emitting layer EM1. Theorganic layer OR3 includes a light emitting layer EM3. The lightemitting layer EM3 is formed of a material different from the materialsof the light emitting layers EM1 and EM2.

The material of the light emitting layer EM1, the material of the lightemitting layer EM2 and the material of the light emitting layer EM3 arematerials which emit light in different wavelength ranges.

For example, the light emitting layer EM1 is formed of a material whichemits light in a blue wavelength range. The light emitting layer EM2 isformed of a material which emits light in a green wavelength range. Thelight emitting layer EM3 is formed of a material which emits light in ared wavelength range.

Each of the cap layers CP1, CP2 and CP3 is formed of, for example, amultilayer body of transparent thin films. As the thin films, themultilayer body includes a thin film formed of an organic material.These thin films have refractive indices different from each other. Thematerials of the thin films constituting the multilayer body aredifferent from the materials of the upper electrodes UE1, UE2 and UE3and are also different from the materials of the sealing layers SE1, SE2and SE3.

The protective layer 13 is formed of a multilayer body of transparentthin films. For example, as the thin films, the multilayer body includesa thin film formed of an inorganic material and a thin film formed of anorganic material.

Common voltage is applied to the partition 6. This common voltage isapplied to each of the upper electrodes UE1, UE2 and UE3 which are incontact with the side surfaces of the lower portions 61. Pixel voltageis applied to the lower electrodes LE1, LE2 and LE3 through the pixelcircuits 1 provided in subpixels SP1, SP2 and SP3, respectively.

When a potential difference is formed between the lower electrode LE1and the upper electrode UE1, the light emitting layer EM1 of the organiclayer OR1 emits light in a blue wavelength range. When a potentialdifference is formed between the lower electrode LE2 and the upperelectrode UE2, the light emitting layer EM2 of the organic layer OR2emits light in a green wavelength range. When a potential difference isformed between the lower electrode LE3 and the upper electrode UE3, thelight emitting layer EM3 of the organic layer OR3 emits light in a redwavelength range.

FIG. 4 is a diagram showing an example of the configuration of thedisplay elements 201 to 203. Here, in the example, this specificationassumes that each lower electrode corresponds to an anode and each upperelectrode corresponds to a cathode.

The display element 201 includes the organic layer OR1 between the lowerelectrode LE1 and the upper electrode UE1.

In the organic layer OR1, a hole injection layer HIL1, a hole transportlayer HTL1, an electron blocking layer EBL1, the light emitting layerEM1, a hole blocking layer HBL1, an electron transport layer ETL1 and anelectron injection layer EIL1 are stacked in this order.

The cap layer CP1 includes a first transparent layer TL11 and a secondtransparent layer TL12. The first transparent layer TL11 is provided onthe upper electrode UE1. The second transparent layer TL12 is providedon the first transparent layer TL11. The sealing layer SE1 is providedon the second transparent layer TL12.

The display element 202 includes the organic layer OR2 between the lowerelectrode LE2 and the upper electrode UE2.

In the organic layer OR2, a hole injection layer HIL2, a hole transportlayer HTL2, an electron blocking layer EBL2, the light emitting layerEM2, a hole blocking layer HBL2, an electron transport layer ETL2 and anelectron injection layer EIL2 are stacked in this order.

The cap layer CP2 includes a first transparent layer TL21 and a secondtransparent layer TL22. The first transparent layer TL21 is provided onthe upper electrode UE2. The second transparent layer TL22 is providedon the first transparent layer TL21. The sealing layer SE2 is providedon the second transparent layer TL22.

The display element 203 includes the organic layer OR3 between the lowerelectrode LE3 and the upper electrode UE3.

In the organic layer OR3, a hole injection layer HIL3, a hole transportlayer HTL3, an electron blocking layer EBL3, the light emitting layerEM3, a hole blocking layer HBL3, an electron transport layer ETL3 and anelectron injection layer EIL3 are stacked in this order.

The cap layer CP3 includes a first transparent layer TL31 and a secondtransparent layer TL32. The first transparent layer TL31 is provided onthe upper electrode UE3. The second transparent layer TL32 is providedon the first transparent layer TL31. The sealing layer SE3 is providedon the second transparent layer TL32.

The first transparent layers TL11, TL21 and TL31 are transparent organiclayers each formed of an organic material, and are high refractivelayers having refractive indices greater than those of the upperelectrodes UE1, UE2 and UE3. For example, the refractive index of eachof the first transparent layers TL11, TL21 and TL31 is greater than orequal to 1.7 but less than or equal to 2.0.

The second transparent layers TL12, TL22 and TL32 are transparentorganic layers each formed of an organic material, and are lowrefractive layers having refractive indices less than those of the firsttransparent layers TL11, TL21 and TL31. For example, the refractiveindex of each of the second transparent layers TL12, TL22 and TL32 isgreater than or equal to 1.3 but less than or equal to 1.6.

The refractive indices of the sealing layers SE1, SE2 and SE3 which arein contact with the second transparent layers TL12, TL22 and TL32 aregreater than those of the second transparent layers TL12, TL22 and TL32.For example, the refractive index of each of the sealing layers SE1, SE2and SE3 is greater than or equal to 1.7 but less than or equal to 2.0.

As the organic material for forming the second transparent layers TL12,TL22 and TL32, fluorine resin in which the main chain consists of carbonand which contains fluorine in a substituent is desirable. For example,each of the second transparent layers TL12, TL22 and TL32 can be formedof at least one of polytetrafluoroethylene (PTFE), polyvinylidenefluoride (PVDF) and 2-(perfluorohexyl)ethyl acrylate. The refractiveindex of polytetrafluoroethylene is 1.35. The refractive index ofpolyvinylidene fluoride is 1.42. The refractive index of2-(perfluorohexyl)ethyl acrylate is 1.35.

As another material for forming the second transparent layers TL12, TL22and TL32, lithium fluoride can be considered. The refractive index oflithium fluoride is 1.4. It should be noted that lithium fluoride isvery hygroscopic.

To the contrary, the organic materials described above such aspolytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF) and2-(perfluorohexyl)ethyl acrylate have a less hygroscopic propertycompared to lithium fluoride and do not exhibit a deliquescent property.Thus, these organic materials can stably maintain the state of a thinfilm even if they are exposed to air.

The second transparent layers TL12, TL22 and TL32 to which these organicmaterials are applied can be formed by a method such as vapor depositionbased on resistive heating, vapor deposition based on ion beams orsputtering. The film thickness of each of these second transparentlayers TL12, TL22 and TL32 is, for example, 20 nm to 500 nm.

Each of the cap layers CP1, CP2 and CP3 described above may be a stackedlayer body consisting of three or more layers.

It should be noted that each of the organic layers OR1, OR2 and OR3 mayinclude, in addition to the functional layers described above, otherfunctional layers such as a carrier generation layer as needed, or atleast one of the above functional layers may be omitted.

The above functional layers are individually formed for each of thedisplay elements 201 to 203. Thus, the thickness of each of the abovefunctional layers may differ depending on the display element.

When this specification focuses attention on the same functional layer,the functional layer of one of the display elements 201 to 203 may beformed of a material different from that of the functional layers of theother two display elements, or all of the functional layers of thedisplay elements 201 to 203 may be formed of materials different fromeach other.

Further, the layer structure of one of the display elements 201 to 203may be different from that of the other two display elements, or all ofthe layer structures of the display elements 201 to 203 may be differentfrom each other. For example, when this specification focuses attentionon one of the functional layers, one of the display elements 201 to 203may not include this functional layer, or only one of the displayelements 201 to 203 may include the functional layer. When thisspecification focuses attention on one of the functional layers, forexample, this functional layer may comprise a multilayer structure inone of the display elements 201 to 203.

The first transparent layers TL11, TL21 and TL31 are spaced apart fromeach other and are individually formed. Thus, all of the firsttransparent layers TL11, TL21 and TL31 may be formed of the samematerial, or one of the first transparent layers TL11, TL21 and TL31 maybe formed of a material different from that of the other two transparentlayers, or all of the first transparent layers TL11, TL21 and TL31 maybe formed of materials different from each other.

The second transparent layers TL12, TL22 and TL32 are spaced apart fromeach other and are individually formed. Thus, all of the secondtransparent layers TL12, TL22 and TL32 may be formed of the samematerial, or one of the second transparent layers TL12, TL22 and TL32may be formed of a material different from that of the other twotransparent layers, or all of the second transparent layers TL12, TL22and TL32 may be formed of materials different from each other.

All of the thicknesses of the first transparent layers TL11, TL21 andTL31 may be the same as each other, or may be different from each other.

All of the thicknesses of the second transparent layers TL12, TL22 andTL32 may be the same as each other, or may be different from each other.

For example, all of the thicknesses of the second transparent layersTL12, TL22 and TL32 are the same as each other. The thickness of thefirst transparent layer TL11 in the display element 201 for blue is lessthan that of the first transparent layer TL31 in the display element 203for red.

In the display element 201, the thickness of the second transparentlayer TL12 is greater than that of the first transparent layer TL11. Inthe display element 203, the thickness of the first transparent layerTL31 is less than that of the second transparent layer TL32.

All of the layer structures of the cap layers CP1 to CP3 may be the sameas each other, or the layer structure of one of the cap layers CP1 toCP3 may be different from that of the other two cap layers, or all ofthe layer structures of the cap layers CP1 to CP3 may be different fromeach other.

In the example shown in FIG. 4 , in the display element 201, the upperelectrode UE1 functions as an etching stopper layer when dry etching isapplied to the sealing layer SE1. In the display element 202, the upperelectrode UE2 functions as an etching stopper layer when dry etching isapplied to the sealing layer SE2. In the display element 203, the upperelectrode UE3 functions as an etching stopper layer when dry etching isapplied to the sealing layer SE3.

When dry etching is applied to each of an etching stopper layer and asealing layer on the same condition, and the etching rate of the etchingstopper layer (an upper electrode) is compared with that of the sealinglayer, the etching rate of the etching stopper layer is less than thatof the sealing layer. In this configuration, when dry etching isperformed for a stacked layer body in which the sealing layer is stackedon the etching stopper layer, while the sealing layer is removed, theprogress of etching can be stopped in the etching stopper layer.

The upper electrodes UE1, UE2 and UE3 which function as etching stopperlayers are formed of a material different from the materials of the rib5 and the sealing layers SE1, SE2 and SE3. For example, the rib 5 andthe sealing layers SE1, SE2 and SE3 are formed of silicon nitride. Theupper electrodes UE1, UE2 and UE3 are formed of an alloy of magnesiumand silver, which is a material having a high resistance to dry etchingcompared to silicon nitride.

Now, this specification explains an example of the manufacturing methodof the display device DSP.

FIG. 5 is a flow diagram for explaining an example of the manufacturingmethod of the display device DSP.

The manufacturing method shown here roughly includes the process ofpreparing a processing substrate SUB comprising subpixels SP1, SP2 andSP3 (step ST1), the process of forming the display element 201 ofsubpixel SP1 (step ST2), the process of forming the display element 202of subpixel SP2 (step ST3) and the process of forming the displayelement 203 of subpixel SP3 (step ST4).

In step ST1, first, the processing substrate SUB is prepared by formingthe lower electrode LE1 of subpixel SP1, the lower electrode LE2 ofsubpixel SP2, the lower electrode LE3 of subpixel SP3, the rib 5 and thepartition 6 above the substrate 10. As shown in FIG. 3 , the circuitlayer 11 and the insulating layer 12 are also formed between thesubstrate 10 and the lower electrodes LE1, LE2 and LE3.

In step ST2, first, a first thin film 31 including the light emittinglayer EM1 is formed over subpixel SP1, subpixel SP2 and subpixel SP3(step ST21). The first thin film 31 is a stacked layer body of theorganic layer OR1, upper electrode UE1, cap layer CP1 and sealing layerSE1 shown in FIG. 3 . Subsequently, a first resist 41 patterned into apredetermined shape is formed on the first thin film 31 (step ST22).Subsequently, part of the first thin film 31 is removed by etching usingthe first resist 41 as a mask (step ST23). At this time, for example,the first thin film 31 provided in subpixel SP2 and subpixel SP3 isremoved. Subsequently, the first resist 41 is removed (step ST24). Inthis way, subpixel SP1 is formed. Subpixel SP1 comprises the displayelement 201 comprising the first thin film 31 having a predeterminedshape.

In step ST3, first, a second thin film 32 including the light emittinglayer EM2 is formed over subpixel SP1, subpixel SP2 and subpixel SP3(step ST31). The second thin film 32 is a stacked layer body of theorganic layer OR2, upper electrode UE2, cap layer CP2 and sealing layerSE2 shown in FIG. 3 . Subsequently, a second resist 42 patterned into apredetermined shape is formed on the second thin film 32 (step ST32).Subsequently, part of the second thin film 32 is removed by etchingusing the second resist 42 as a mask (step ST33). At this time, forexample, the second thin film 32 provided in subpixel SP1 and subpixelSP3 is removed. Subsequently, the second resist 42 is removed (stepST34). In this way, subpixel SP2 is formed. Subpixel SP2 comprises thedisplay element 202 comprising the second thin film 32 having apredetermined shape.

In step ST4, first, a third thin film 33 including the light emittinglayer EM3 is formed over subpixel SP1, subpixel SP2 and subpixel SP3(step ST41). The third thin film 33 is a stacked layer body of theorganic layer OR3, upper electrode UE3, cap layer CP3 and sealing layerSE3 shown in FIG. 3 . Subsequently, a third resist 43 patterned into apredetermined shape is formed on the third thin film 33 (step ST42).Subsequently, part of the third thin film 33 is removed by etching usingthe third resist 43 as a mask (step ST43). At this time, for example,the third thin film 33 provided in subpixel SP1 and subpixel SP2 isremoved. Subsequently, the third resist 43 is removed (step ST44). Inthis way, subpixel SP3 is formed. Subpixel SP3 comprises the displayelement 203 comprising the third thin film 33 having a predeterminedshape.

The detailed illustrations of the second thin film 32, the second resist42, the third thin film 33 and the third resist 43 are omitted.

Now, this specification explains step ST1 and step ST2 with reference toFIG. 6 to FIG. 12 . The section shown in each of FIG. FIG. 6 to FIG. 12corresponds to, for example, the section taken along the A-B line ofFIG. 2 .

First, in step ST1, as shown in FIG. 6 , the processing substrate SUB isprepared. The process of preparing the processing substrate SUB includesthe process of forming the circuit layer 11 on the substrate 10, theprocess of forming the insulating layer 12 on the circuit layer 11, theprocess of forming the lower electrode LE1 of subpixel SP1, the lowerelectrode LE2 of subpixel SP2 and the lower electrode LE3 of subpixelSP3 on the insulating layer 12, the process of forming the rib 5comprising the apertures AP1, AP2 and AP3 overlapping the lowerelectrodes LE1, LE2 and LE3, respectively, and the process of formingthe partition 6 including the lower portion 61 provided on the rib 5 andthe upper portion 62 provided on the lower portion 61 and protrudingfrom the side surfaces of the lower portion 61. In each of FIG. 7 toFIG. 12 , the illustrations of the substrate 10 and the circuit layer 11lower than the insulating layer 12 are omitted.

The rib 5 is formed of, for example, silicon nitride.

Of the partition 6, at least the lower portion 61 is formed of aconductive material.

Subsequently, in step ST21, as shown FIG. 7 , the first thin film 31 isformed over subpixel SP1, subpixel SP2 and subpixel SP3. The process offorming the first thin film 31 includes, on the processing substrateSUB, the process of forming the organic layer OR1 including the lightemitting layer EM1, the process of forming the upper electrode UE1 onthe organic layer OR1, the process of forming the first transparentlayer TL11 of the cap layer CP1 on the upper electrode UE1, the processof forming the second transparent layer TL12 of the cap layer CP1 on thefirst transparent layer TL11 and the process of forming the sealinglayer SE1 on the second transparent layer TL12. Thus, in the exampleshown in the figure, the first thin film 31 includes the organic layerOR1, the upper electrode UE1, the cap layer CP1 and the sealing layerSE1.

The organic layer OR1 is formed on each of the lower electrode LE1, thelower electrode LE2 and the lower electrode LE3 and is also formed onthe partition 6. Of the organic layer OR1, the portion formed on eachupper portion 62 is spaced apart from the portion formed on each of thelower electrodes LE1, LE2 and LE3. The various functional layers and thelight emitting layer EM1 of the organic layer OR1 are formed by a vapordeposition method.

The upper electrode UE1 is formed on the organic layer OR1 immediatelyabove each of the lower electrodes LE1, LE2 and LE3, covers the rib 5and is in contact with the lower portions 61 of the partition 6. Theupper electrode UE1 is also formed on the organic layer OR1 immediatelyabove each upper portion 62. Of the upper electrode UE1, the portionwhich is formed immediately above each upper portion 62 is spaced apartfrom the portion which is formed immediately above each of the lowerelectrodes LE1, LE2 and LE3. The upper electrode UE1 is formed of analloy of magnesium and silver by a vapor deposition method.

The first transparent layer TL11 of the cap layer CP1 is formed on theupper electrode UE1 immediately above each of the lower electrodes LE1,LE2 and LE3, and is also formed on the upper electrode UE1 immediatelyabove each upper portion 62. Of the first transparent layer TL11, theportion which is formed immediately above each upper portion 62 isspaced apart from the portion which is formed immediately above each ofthe lower electrodes LE1, LE2 and LE3. For example, the firsttransparent layer TL11 is formed of an organic material by a vapordeposition method.

The second transparent layer TL12 of the cap layer CP1 is formed on thefirst transparent layer TL11 immediately above each of the lowerelectrodes LE1, LE2 and LE3, and is also formed on the first transparentlayer TL11 immediately above each upper portion 62. Of the secondtransparent layer TL12, the portion which is formed immediately aboveeach upper portion 62 is spaced apart from the portion which is formedimmediately above each of the lower electrodes LE1, LE2 and LE3. Forexample, the second transparent layer TL12 is formed of an organicmaterial by a vapor deposition method. The second transparent layer TL12is formed of an organic material which is different from the firsttransparent layer TL11. Further, the refractive index of the secondtransparent layer TL12 is less than that of the first transparent layerTL11.

The sealing layer SE1 is formed so as to cover the second transparentlayer TL12 and the partition 6. In other words, the sealing layer SE1 isformed on the second transparent layer TL12 immediately above each ofthe lower electrodes LE1, LE2 and LE3, and is also formed on the secondtransparent layer TL12 immediately above each upper portion 62.Moreover, the sealing layer SE1 is in contact with the lower portion 61of the partition 6. In the sealing layer SE1, the portion which isformed immediately above each upper portion 62 is continuous with theportion which is formed immediately above each of the lower electrodes.The sealing layer SE1 is formed of, for example, silicon nitride. Thesealing layer SE1 is formed by, for example, a CVD method.

Subsequently, in step ST22, as shown in FIG. 8 , the patterned firstresist 41 is formed on the sealing layer SE1. The first resist 41 coversthe first thin film 31 of subpixel SP1, and the first thin film 31 isexposed from the first resist 41 in subpixels SP2 and SP3. Thus, thefirst resist 41 overlaps the sealing layer SE1 located immediately abovethe lower electrode LE1. The first resist 41 extends from subpixel SP1to the upper side of the partition 6. On the partition 6 betweensubpixel SP1 and subpixel SP2, the first resist 41 is provided on thesubpixel SP1 side (the left side of the figure), and the sealing layerSE1 is exposed from the first resist 41 on the subpixel SP2 side (theright side of the figure). The sealing layer SE1 is exposed from thefirst resist 41 in subpixel SP2 and subpixel SP3.

Subsequently, in step ST23, as shown in FIG. 9 to FIG. 11 , etching isapplied using the first resist 41 as a mask. By this process, the firstthin film 31 exposed from the first resist 41 in subpixels SP2 and SP3is removed, and the first thin film 31 remains in subpixel SP1.

The process of removing the first thin film 31 is, for example, asfollows.

First, as shown in FIG. 9 , dry etching is performed using the firstresist 41 as a mask to remove the sealing layer SE1 exposed from thefirst resist 41. By this process, of the cap layer CP1, part of thesecond transparent layer TL12 is exposed from the sealing layer SE1.

Subsequently, as shown in FIG. 10 , ashing (dry etching for emittingoxygen plasma) is performed using the first resist 41 as a mask toremove the second transparent layer TL12 exposed from the sealing layerSE1.

Subsequently, ashing is performed using the first resist 41 as a mask toremove the first transparent layer TL11 exposed from the secondtransparent layer TL12. By this process, part of the upper electrode UE1is exposed from the cap layer CP1.

Subsequently, as shown in FIG. 11 , wet etching is performed using thefirst resist 41 as a mask to remove the upper electrode UE1 exposed fromthe first transparent layer TL11.

Subsequently, asking is performed using the first resist 41 as a mask toremove the organic layer OR1 exposed from the upper electrode UE1.

In this way, the lower electrode LE2 is exposed in subpixel SP2, and therib 5 surrounding the lower electrode LE2 is exposed. In subpixel SP3,the lower electrode LE3 is exposed, and the rib 5 surrounding the lowerelectrode LE3 is exposed. Of the partition 6 between subpixel SP1 andsubpixel SP2, the subpixel SP2 side is exposed. Further, the partition 6between subpixel SP2 and subpixel SP3 is exposed.

Subsequently, in step ST24, as shown in FIG. 12 , the first resist 41 isremoved. Thus, the sealing layer SE1 of subpixel SP1 is exposed. Throughthese steps ST21 to ST24, the display element 201 is formed in subpixelSP1. The display element 201 consists of the lower electrode LE1, theorganic layer OR1 including the light emitting layer EM1, the upperelectrode UE1, the first transparent layer TL11 and the secondtransparent layer TL12. The display element 201 is covered with thesealing layer SE1.

A stacked layer body of the organic layer OR1 including the lightemitting layer EM1, the upper electrode UE1, the first transparent layerTL11, the second transparent layer TL12 and the sealing layer SE1 isformed on the partition 6 between subpixel SP1 and subpixel SP2. Thestacked layer body located on the partition 6 is spaced apart from theorganic layer OR1, the upper electrode UE1, the first transparent layerTL11, the second transparent layer TL12 and the sealing layer SE1constituting the display element 201. Of the partition 6, the portion onthe subpixel SP1 side is covered with the sealing layer SE1. It shouldbe noted that the stacked layer body on the partition 6 shown in FIG. 12is completely removed in some cases.

Steps ST31 to ST34 shown in FIG. 5 are similar to steps ST21 to ST24described above. Through these steps ST31 to ST34, the display element202 is formed in subpixel SP2 shown in FIG. 3 . The display element 202consists of the lower electrode LE2, the organic layer OR2 including thelight emitting layer EM2, the upper electrode UE2, the first transparentlayer TL21 and the second transparent layer TL22. The display element202 is covered with the sealing layer SE2.

Steps ST41 to ST44 shown in FIG. 5 are also similar to steps ST21 toST24 described above. Through these steps ST41 to ST44, the displayelement 203 is formed in subpixel SP3 shown in FIG. 3 . The displayelement 203 consists of the lower electrode LE3, the organic layer OR3including the light emitting layer EM3, the upper electrode UE3, thefirst transparent layer TL31 and the second transparent layer TL32. Thedisplay element 203 is covered with the sealing layer SE3.

In the present embodiment, the display elements 201 to 203 comprise thecap layers CP1 to CP3, respectively, which function as opticaladjustment layers. Thus, the light emitted from the light emittinglayers EM1 to EM3 is reflected on the interface between the first andsecond transparent layers constituting the cap layers CP1 to CP3,respectively, and is reflected on the upper electrode again. By themicrocavity effect using such interference of reflected light, the lightextraction efficiency for each display element can be improved.

This optical adjustment layer is formed as a stacked layer bodyconsisting of a low refractive layer and a high refractive layer. In themanufacturing method of the display device described above, the first tothird thin films each including the optical adjustment layer arepatterned for each subpixel. At this time, as each layer constitutingthe optical adjustment layer is formed of an organic material, thelayers can be easily and continuously removed by an ashing process. Inaddition, in the ashing process, oxygen plasma is emitted whilespreading. Therefore, as shown in FIG. 9 , both the low refractive layerand the high refractive layer can be assuredly removed immediately underthe protrusion 622 of the partition 6 and immediately under theprotrusion 623 of the partition 6. Thus, the generation of the residueof the organic materials is prevented, thereby preventing the reductionin reliability.

Further, as the organic material for forming each of the low refractivelayer and the high refractive layer, a material having a hightransparency and a predetermined refractive index can be applied. Thus,the number of choices for the applicable materials is increased. Whenthe organic material is removed, an ashing process is applied. Further,the low refractive layer and the high refractive layer can becontinuously removed. Thus, the process becomes more flexible and theprocessing time is also shortened compared to wet etching for removingthe layers by a predetermined etchant.

As explained above, the present embodiment can provide a display devicewhich can prevent the reduction in reliability and have an improvedmanufacturing yield, and a manufacturing method thereof.

All of the display devices and manufacturing methods thereof that can beimplemented by a person of ordinary skill in the art through arbitrarydesign changes to the display device and manufacturing method thereofdescribed above as the embodiment of the present invention come withinthe scope of the present invention as long as they are in keeping withthe spirit of the present invention.

Various modification examples which may be conceived by a person ofordinary skill in the art in the scope of the idea of the presentinvention will also fall within the scope of the invention. For example,even if a person of ordinary skill in the art arbitrarily modifies theabove embodiment by adding or deleting a structural element or changingthe design of a structural element, or by adding or omitting a step orchanging the condition of a step, all of the modifications fall withinthe scope of the present invention as long as they are in keeping withthe spirit of the invention.

Further, other effects which may be obtained from the above embodimentand are self-explanatory from the descriptions of the specification orcan be arbitrarily conceived by a person of ordinary skill in the artare considered as the effects of the present invention as a matter ofcourse.

What is claimed is:
 1. A manufacturing method of a display device,comprising: preparing a processing substrate by forming a first lowerelectrode and a second lower electrode above a substrate, forming a ribon the first lower electrode and the second lower electrode, the ribbeing formed of a first inorganic insulating material and including afirst aperture overlapping the first lower electrode and a secondaperture overlapping the second lower electrode, and forming a partitionon the rib, the partition including a lower portion on the rib andbetween the first aperture and the second aperture, and an upper portionon the lower portion and extending beyond a side surface of the lowerportion; forming a first organic layer on the rib and the partition, thefirst organic layer including a first light-emitting layer and being incontact with the first lower electrode at the first aperture; forming afirst upper electrode on the first organic layer; forming a firsttransparent layer on the first upper electrode, the first transparentlayer being formed of a first organic material; forming a secondtransparent layer on the first transparent layer, the second transparentlayer being formed of a second organic material different from the firstorganic material; forming a first sealing layer on the secondtransparent layer, the first sealing layer being formed of a secondinorganic insulating material; forming a first patterned resist on thefirst sealing layer, the first patterned resist covering a first portionof the first sealing layer above the first lower electrode and a secondportion of the first sealing layer above a first part of the upperportion of the partition, and the first patterned resist exposing athird portion of the first sealing layer above the second lowerelectrode and a fourth portion of the first sealing layer above a secondpart of the upper portion of the partition; removing the third portionof the first sealing layer to expose a portion of the second transparentlayer by a first dry etching; removing the portion of the secondtransparent layer to expose a portion of the first transparent layer bya second dry etching using an oxygen plasma; removing the portion of thefirst transparent layer to expose a portion of the first upper electrodeby the second dry etching; removing the portion of the first upperelectrode to expose a portion of the first organic layer by a first wetetching; removing the portion of the first organic layer by a third dryetching using the oxygen plasma, and removing the first patternedresist.
 2. The manufacturing method of a display device according toclaim 1, further comprising: after removing the first patterned resist,forming a second organic layer above the first lower electrode, on thesecond lower electrode and on the upper portion of the partition, thesecond organic layer including a second light-emitting layer and beingin contact with the second lower electrode at the second aperture;forming a second upper electrode on the second organic layer; forming athird transparent layer on the second upper electrode, the thirdtransparent layer being formed of a third organic material; forming afourth transparent layer on the third transparent layer, the fourthtransparent layer being formed of a fourth organic material differentfrom the third organic material; forming a second sealing layer on thefourth transparent layer, the second sealing layer being formed of athird inorganic insulating material; forming a second patterned resiston the second sealing layer, the second patterned resist covering afirst portion of the second sealing layer above the second lowerelectrode and a second portion of the second sealing layer above a thirdpart of the upper portion of the partition, and the second patternedresist exposing a third portion of the second sealing layer above thefirst lower electrode and a fourth portion of the second sealing layerabove a fourth part of the upper portion of the partition; removing thethird portion of the second sealing layer to expose a portion of thefourth transparent layer by a fourth dry etching; removing the portionof the fourth transparent layer to expose a portion of the thirdtransparent layer by a fifth dry etching using the oxygen plasma;removing the portion of the third transparent layer to expose a portionof the second upper electrode by the fifth dry etching; removing theportion of the second upper electrode to expose a portion of the secondorganic layer by a second wet etching; removing the portion of thesecond organic layer by a sixth dry etching using the oxygen plasma, andremoving the second patterned resist, wherein the first light-emittinglayer emits a light of a first color, and the second light-emittinglayer emits a light of a second color different from the first color. 3.The manufacturing method of a display device according to claim 1,wherein a second refractive index of the second organic material issmaller than a first refractive index of the first organic material. 4.The manufacturing method of a display device according to claim 3,wherein a fifth refractive index of the first sealing layer is greaterthan the second refractive index of the second organic material.
 5. Themanufacturing method of a display device according to claim 1, wherein afirst refractive index of the first organic material is greater than orequal to 1.7, and a second refractive index of the second organicmaterial is less than or equal to 1.6.
 6. The manufacturing method of adisplay device according to claim 1, wherein the forming the lowerportion of the partition includes a sputtering deposition of aconductive material, and the forming the first upper electrode includeselectrically contacting the first upper electrode to the lower portionof the partition.
 7. The manufacturing method of a display deviceaccording to claim 1, wherein the forming the first upper electrodeincludes vapor depositing an alloy of magnesium and silver.
 8. Themanufacturing method of a display device according to claim 2, wherein athird refractive index of the third organic material is smaller than afourth refractive index of the fourth organic material.
 9. Themanufacturing method of a display device according to claim 8, wherein asixth refractive index of the second sealing layer is greater than thefourth refractive index of the fourth organic material.
 10. Themanufacturing method of a display device according to claim 2, wherein athird refractive index of the third organic material is greater than orequal to 1.7, and a fourth refractive index of the fourth organicmaterial is less than or equal to 1.6.
 11. The manufacturing method of adisplay device according to claim 2, wherein the forming the lowerportion of the partition includes a sputtering deposition of aconductive material, and the forming the second upper electrode includeselectrically contacting the second upper electrode to the lower portionof the partition.
 12. The manufacturing method of a display deviceaccording to claim 2, wherein the forming the second upper electrodeincludes vapor depositing an alloy of magnesium and silver.
 13. Themanufacturing method of a display device according to claim 2, whereinthe first organic material and the third organic material are a sameorganic material.
 14. The manufacturing method of a display deviceaccording to claim 2, wherein the first organic material is differentfrom the third organic material.
 15. The manufacturing method of adisplay device according to claim 2, wherein the second organic materialand the fourth organic material are a same organic material.
 16. Themanufacturing method of a display device according to claim 2, whereinthe second organic material is different from the fourth organicmaterial.
 17. The manufacturing method of a display device according toclaim 2, wherein a first thickness of the first transparent layer isequal to a third thickness of the third transparent layer.
 18. Themanufacturing method of a display device according to claim 2, wherein afirst thickness of the first transparent layer is different from a thirdthickness of the third transparent layer.
 19. The manufacturing methodof a display device according to claim 2, wherein a second thickness ofthe second transparent layer is equal to a fourth thickness of thefourth transparent layer.
 20. The manufacturing method of a displaydevice according to claim 2, wherein a second thickness of the secondtransparent layer is different from a fourth thickness of the fourthtransparent layer.